Electronic cameras of recent years can record many images to a record medium. Thus, it is becoming bothersome to retrieve a desired image from many images that have been photographed and recorded. In related art, an index display function, a calendar display function, a folder display function, and so forth that allow many images to be efficiently checked on a screen are known.
The index display function is a function of successively displaying many images recorded on a record medium on an index screen that is a multiply segmented screen. The calendar display function is a function of reducing images every photographed year, month, or day and displaying the reduced images on one screen. The folder display function is a function of reducing images contained in a folder and displaying the reduced images.
However, the index display function simply displays a plurality of images of many images on one screen. In the calendar display function, if there are many images photographed on the same date, retrieval efficiency deteriorates. The folder display function necessitates photographed images to be separately recorded in folders in advance. A method of categorizing image data of moving image data as groups is described in Japanese Patent Application Laid-Open No. HEI 10-254746. In this related art, as a method of categorizing image data as groups, image data are categorized as groups on the basis of photographed locations and photographed times.
Japanese Patent Application Laid-Open No. HEI 10-254746 describes that top images of individual groups are multi-segment displayed. By designating a desired image from those, a group is selected and image data registered to the group are successively reproduced.
In the display method described in Japanese Patent Application Laid-Open No. HEI 10-254746, photographed images are hierarchically categorized as groups. The user browses representative images of individual groups, designates his or her desired group from the representative images, and then selects his or her desired image in the designated group. However, with representative images, the user is not able to easily know other images in the groups. Thus, it is thought that the related art is not user-friendly to retrieve a desired image from many images.